Apparatus for generating respirable air from liquemed gases



June 19, m3. 1,459,158

LM-LHSSE APPARATUS FOR GENERATING RESPIRABLE AIR FROM LIQUEFIED GASES ed July 19. 1920 Patent dune 19, 1923.

4 nnoromi Lissa, or BERLIN, onamenr.

Application filed. July 19,

T 0 all whom it may concern:

Be it known that I Lnorono LISSE, a subject of the German l lmp'ire, and a resident of Berlin, Germany, have invented certain new and useful Apparatus for Generating Respirable Air from Liquefied Gases, of which the following is a specification.

My invention relates to apparatus for generating respirable air from liquid air.

In prior apparatus of this type the liquid air was ermitted to evaporatecontinuous- 1y. No means was rovided-for preventing the evaporation of the liquid while the apparatus was not in use, and no provision was made to facilitate evaporation when the apparatus was placed in use.

The object of my invention is an improved apparatus provided with means by which the evaporation of the li uid air may be accuratel controlled, so t at, air suitable for inhaling through the mask of a breathing apparatus as used in aircraft, for instance, is generated only when required-and the evaporation of the liquid can then be facilitated. I

An apparatus embodying my invention is illustrated by way of example in the accompanying drawing.

Referring to the drawing a is a storage vessel containing the liquid air. The liquid air contained in a vessel a protected by a vacuum acket b, is, as soon as respirable air is required, caused to evaporate, for instance by introducing heat into the vessel through a bar or rod 2', fixed to a screw cap g. on a supply of respirableair is required, heat is introduced into the liquid -container by means of a heated bar or rod 2' fixed to a screw cap g. In consequence of the evaporation of the liquid pressure is generated in the vessel a and a small quantity of liquid rises in the pipe and reaches the first evap-' oration chamber d. The vapours produced then pass into a second evaporation chamber d and even if desired into a third one, in order to induce the vapours to deposit any liquid carried along by them. From the last chamber the vapor passes through a coil h, to a pressure regulating rese'rvior o and hence through a flexible tube m to the gas mask u of the user. In this manner the vapours are exposed to large contact surfaces and are thus dried and also warmed by the outside air and thus reach the mask in a completely dry andsufiiciently heated state.

1920. Eerie! Ho. 39?,335.

chamber d and hence to the respiratory mask for inhaling. For this purpose the space of the vowel a above the liquid air is in communication withv the atmosphere through a coiled pipe 2, the outlet of which 15 controlled by throttle valve 'f. The position of the valve 7, is preferabl indicated by means of a pointer z, fixe upon the valve operating disc and movin over a stationary graduated scales. on the valve is throttled a littlethe pressure on the liquid forces a small quantity of liquid through the pipe is into the evaporation chamber 01. The uantity of liquid forced into the chamber increases as the valve 7 1s throttled and reaches its maximum when the valve is closed entirely. In order to avoid dangerous over-pressures safety valves such as p, p, "may be provided in proper places.

Preferably a Dewar-Heyland vessel is used as container for the liquid air, the vacuum space 6 of which contains an ab sorbent for gases or humidity. which may enter this space;

It willbe understood that I do not limit myself to the exact details of the construc-. tion illustrated, but that these may be varied within the limit of the claims.

What I claim as m invention and desire to secure by Letters atent is:'

1. In a paratus for generating respirable air from iquid air container with means for facilitating the evaporation, a pipe through which said liquid container communicates with the atmosphere, a throttle valve at the outlet of said pipe, an evaporation chamber a pipe connecting said container with said chamber, said chamber being supplied with more or less 1i uid the more or less said valve is throttled.

2. In apparatus for generating respirable air from liquid air, the combination of a liquid air container, a rod adapted to be heated and introduced into the container to raise the temperature and to increase the evaporation within said container, a pipe through which said liquid container communicates with the atmosphere, a throttle valve'at the outletof said pipe, an eva ration chamber, a pipe connecting said liquid container with mid chamber, saidphambor beingsupplied with more oriess liquid the more or less said valve is thrott'ied.

3. The im raved breathing apparatus with liquid air supply, comprising in combimitionio iiq uid air container in the form of a Dewar-Heyland vessel, o pipe through which said vessei. communicates with the of;- 'mosphere, a, :throtflo valve at ihe free and of said pipe a heated rodadopted io be introduced into said oonwliinor to roiso tho temperature within it, "movopomihiom id ombe)? a pipe connecting said chamber Wiiih.

sai oomtoiiwi a second evaporation chammagmas her, a; pipe conneci,"saidsecond chamber with said first evaporation ohambei, a'pre ssuro regulating reservoir, a coiil connecting said regulating resoivoir with said iast evaporation chamber, a, gas mask and & fie);- iioio tube connecting said mask with said pressuio roguiatin chamber,

in 'tostimony W oreof I a my signw time in presence of two Wiinossos.

LEOPULD LESSE.

Witnesses: o PETER MEFFERT, Fm'rz LUNDBURG; 

